“Whoa! It’s like Spotify but for academic articles.”

Instant Access to Thousands of Journals for just $40/month

Try 2 weeks free now

Using the Boiling Point of Water to Learn about Hydrogen Bonds

quick fix Using the Boiling Point of Water to Learn about Hydrogen Bonds SuSan Offner AbstrAct The boiling point of water is 300°C higher than expected because of hydrogen bonds. Key Words: Water; hydrogen bonds; boiling point. I then fill in the boiling points as follows. I round to the nearest whole number, but here I give the actual numbers for reference. Absolute zero is –273°C, or 0°Kelvin. H2 = –252.87°C N2 = –195.79°C The boiling point of water can be used to illustrate the importance of O2 = –182.95°C hydrogen bonds in living systems. The boiling point of a compound is the temperature at which a liquid becomes CO2 = –78.5°C a gas. All other things being equal, the boiling The boiling point of point should be approximately proportional The value for CO2 is the sublimation point, to molecular weight, since molecules are held when dry ice, a solid, becomes a gas. a compound is the together by weak forces that are roughly proI then ask students to predict the boiling portional to mass. When the temperature is point of H2O. They admit that it should be temperature at which high enough to separate the individual molaround –200°C. Of course, we all know that a liquid becomes a gas. ecules from each other, they boil, or become water boils at +100°C. The hydrogen bonds a gas. between the water molecules raise its boiling I give students the following chart: point by approximately 300°C, thereby causing water to be a liquid at room temperature and making oceans, rivers, lakes, and, indeed, life possible. This year, my students commented that they knew everything I Molecular Weight Substance Boiling Point was telling them. They knew that N2, O2, and CO2 are all gases at room 2 H2 temperature. But they had never quite thought about it this way. H2O N2 O2 CO2 sUsan oFFner is a biology teacher at lexington high school, lexington, ma 02421; e-mail: soffner@ix.netcom.com. The American Biology Teacher, Vol. 74, no. 5, page 343. issn 0002-7685, electronic issn 1938-4211. ©2012 by national association of biology Teachers. all rights reserved. request permission to photocopy or reproduce article content at the University of california Press’s rights and Permissions Web site at www.ucpressjournals.com/reprintinfo.asp. doi: 10.1525/abt.2012.74.5.12 The american biology Teacher hydrogen bonds http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The American Biology Teacher University of California Press
Loading next page...
1 Page

You’re reading a free preview. Subscribe to read the entire article.

DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy unlimited access and
personalized recommendations from
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $40/month

Try 2 weeks free now

Explore the DeepDyve Library

How DeepDyve Works

Spend time researching, not time worrying you’re buying articles that might not be useful.

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from Springer, Elsevier, Nature, IEEE, Wiley-Blackwell and more.

All the latest content is available, no embargo periods.

See the journals in your area

Simple and Affordable Pricing

14-day free trial. Cancel anytime, with a 30-day money-back guarantee.

Monthly Plan

  • Read unlimited articles
  • Personalized recommendations
  • Print 20 pages per month
  • 20% off on PDF purchases
  • Organize your research
  • Get updates on your journals and topic searches


Best Deal — 25% off

Annual Plan

  • All the features of the Professional Plan, but for 25% off!
  • For the normal price of 10 articles elsewhere, you get one full year of unlimited access to articles.

billed annually